Difference between S460Q and S460QL steel plate - Knowledge

S460Q and S460QL are high-strength structural steel plates, both meeting EN 10025-6 standards for quenched and tempered (Q&T) delivery, offering excellent strength (around 460 MPa minimum yield) and toughness, but the 'L' in S460QL signifies better low-temperature impact performance (tested at -40°C) compared to S460Q (tested at -20°C), making S460QL superior for colder environments, while both are used in heavy construction, bridge building, and heavy machinery requiring reduced weight and high load capacity.

Chemical Composition

S460QChemical Composition
Grade	The Element Max (%)
Grade	C	Si	Mn	P	S	N	B	Cr
S460 Q	0.20	0.80	1.70	0.020-0.025	0.010-0.015	0.015	0.005	1.50
	Cu	Mo	Nb	Ni	Ti	V	Zr
	0.50	0.70	0.06	2.0	0.05	0.12	0.15

S460QLChemical Composition
Grade	The Element Max (%)
Grade	C	Si	Mn	P	S	N	B	Cr
S460 QL	0.20	0.80	1.70	0.020-0.025	0.010-0.015	0.015	0.005	1.50
	Cu	Mo	Nb	Ni	Ti	V	Zr
	0.50	0.70	0.06	2.0	0.05	0.12	0.15

Mechanical Property

Grade	S460Q Mechanical Property
Grade	Thickness	Yield	Tensile	Elongation	Min Impact Energy
S460 Q	mm	Min Mpa	Mpa	Min %	-20	30J
	3<t≦50	460	550-720	17	-20	30J
	50<t≦100	440	550-720	17	-20	30J
	100<t≦150	400	500-670	17	-20	30J

Grade	S460QLMechanical Property
Grade	Thickness	Yield	Tensile	Elongation	Min Impact Energy
S460 QL	mm	Min Mpa	Mpa	Min %	-40	30J
	3<t≦50	460	550-720	17	-40	30J
	50<t≦100	440	550-720	17	-40	30J
	100<t≦150	400	500-670	17	-40	30J

Key Differences: S460Q vs. S460QL

Suffix 'L': Indicates "Low temperature" toughness.

Impact Test: S460QL requires impact testing at -40°C, while S460Q is tested at -20°C (or sometimes -40°C depending on specific requirements).

Application: S460QL is preferred for critical outdoor structures or extreme cold, while S460Q is suitable for general high-strength structural uses where moderate cold performance is enough.

Similarities & Properties

Standard: Both fall under European standard EN 10025-6 for hot-rolled structural steels.

Strength: They provide a minimum yield strength (ReH) of 460 MPa.

Delivery Condition: Both are supplied in a quenched and tempered (Q) condition for enhanced mechanical properties.

Tensile Strength: Range is typically 550-720 MPa, varying slightly with thickness.

Applications: Used for structures needing high strength-to-weight ratio, like cranes, bridges, heavy equipment, and industrial plants.

In essence, S460QL is a tougher, more cold-resistant version of S460Q, offering enhanced performance in demanding, low-temperature conditions.